Pillows are an important piece of bedding that provide comfort and support for the head, neck and upper back. Having a supportive pillow helps ensure that an individual's neck rests in a neutral position while sleeping. This is important as it prevents muscle strain while sleeping: an individual needs this support when he or she is sleeping because the human spine is naturally curved. Having support for the head and neck helps to maintain the proper alignment of these areas of the spine. Sleeping without the adequate support not only has a negative impact on sleep, but it can also result in stiffness in the neck and back.
Having the right pillow is also key to a good night's sleep. Getting an adequate amount of sleep is an important factor for living a healthy life. Getting enough quality sleep requires the individual to have good sleeping conditions. One of the key factors toward getting the full benefits of time in bed is having a pillow that fills the needs of the user. The Great British Sleep Survey of 2012 showed that 67% of respondents rated bodily discomfort as the highest factor keeping them awake at night. Having the right pillow is thus critical for maintaining a sound sleep. Since pillows play an important role in sleep, they will have a considerable impact on an individual's quality of rest and overall well-being.
Many different types of pillows have been designed that use different materials in order to provide the user with a different feel, comfort level or health benefits. These include natural fill pillows (down, feathers or a combination of the two); synthetic fill pillows (which are filled with a man-made fill, customarily polyester; poly cluster fill pillows (which have a synthetic fill of polyester clusters coated with silicone to feel and move like down); foam pillows (which are made of solid pieces or chunks of foam); and memory foam pillows (which are made from a dense, sponge-like material that molds around a user's neck and head for extra support).
The relatively recent introduction of memory foam (which is polyurethane with additional chemicals increasing its viscosity and density, and sometimes referred to as viscoelastic foam or “VEF”) has allowed the creation of pillows that take advantage of the “memory” and other properties of the memory foam. Memory foam pillows are especially suited for sleepers who prefer a firm pillow or have neck or spine issues; however, memory foam pillows tend to have less breathability and make the user hot. When the user removes his or her head from the pillow, the pillow returns to the original shape. This pillow typically reacts to the weight placed upon it and only passively supports the weight based on the thickness or density of the memory foam.
When a pillow made with a filler material is not in use, regardless of which material is chosen as the filler, it should remain in a fluffy state and should be able to provide the level of support needed by the user. However, when the user lays his head down on the body of the pillow made with a filler, the filler becomes compressed and/or can shift. The compressed area of filler is thinner, relatively speaking, than the area of filler that is not compressed, which has a higher density. This causes the pillow to be unable to provide close comfortable support between the user's head and the pillow. This means that after using the pillow for a long period of time, the user may experience discomfort caused by muscle stiffness.
A large number of pillows comprising multiple layers—vertical and/or horizontal—for therapeutically supporting the head and neck of a person lying in a supine position are known in the art. Representative examples are afforded by US 2014/0283305 (Zysman); US 2014/0053336 (Hong-Yuan Cal); US 2013/0291306 (Willingham, et al.); US 2013/0263377 (Wootten, Jr.); US 2012/0204350 (Katsnelson); U.S. 2006/0064819 (Mollett); U.S. 2005/0278852 (Wahrmund et al.); U.S. Pat. No. 8,656,537 (Leifermann, et al.); U.S. Pat. No. 8,607,391 (Poppe, et al.); U.S. Pat. No. 7,735,169 (Wassilefky, et al.); U.S. Pat. No. 8,015,640 (Xi Sun); U.S. Pat. No. 7,856,686 (Kwong Ming Cho); U.S. Pat. No. 7,530,127 (Leifermann); U.S. Pat. No. 7,415,742 (Wassilefky); U.S. Pat. No. 7,051,389 (Wassilefky); U.S. Pat. No. 4,777,855 (Cohen); U.S. Pat. No. 4,803,743 (Greenawalt); U.S. Pat. No. 5,307,532 (Connell); U.S. Pat. No. 5,638,564 (Greenawalt et al.); U.S. Pat. No. 5,689,844 (Liu); WO 2013/063644 (Poppe); US 2012/0102654 (Lee, et al.); WO 2011/141943 (Sciannameo); WO 2010/075296 (Mikkelsen, et al.); US 2006/0064819 (Mollett); US 2005/278852 (Wahrmund, et al.); WO 2005/085123 (Spinks); US 2005/0257320 (Mollett); U.S. Pat. No. 6,101,651 (Yee Keung Tang); U.S. Pat. No. 4,194,255 (Poppe); and U.S. Pat. No. 3,251,078 (Calla).
A need still exists for a pillow made of pillow material, including but not limited to regular foam, memory foam, or fill, that allows different firmness levels for the user, where the firmness levels span the length of the pillow. Further, breathable pillows are also desired to reduce the heat experienced by users.